To obtain hydrocarbons such as oil and gas, wells or wellbores are drilled into the ground through hydrocarbon-bearing subsurface formations. Currently, much current drilling activity involves not only vertical wells but also drilling horizontal wells. In drilling, information from the well itself must be obtained. While seismic data has provided information as to the area to drill and approximate depth of a pay zone, the seismic information can be not totally reliable at great depths. To support the data, information is obtained while drilling through logging while drilling or measuring-while-drilling (MWD) devices. Logging-while-drilling (LWD), or MWD are procedures that have been in use for many years. This procedure is preferred by drillers because it can be accomplished without having to stop drilling to log a hole. This is primarily due to the fact that logging an unfinished hole, prior to setting casing if necessary, can lead to washouts, damaging the drilling work that has already been done. This can stall the completion of the well and delay production. Further, this information can be useful while the well is being drilled to make direction changes immediately.
An important part of drilling operations is the trying to control the direction of drilling in a desired direction. This requires the ability to “see ahead” of the drill bit. There is need for a method of processing acoustic data for looking ahead of the drill bit. This disclosure satisfies that need.